GIS DEVELOPMENT CORP, 5133 145th PLACE SE
A new residence was constructed over a steep slope on a challenging site in the Hilltop area of Bellevue. The house was built elevated over the slope to minimize earthwork and retaining walls.
Due to the steep topography, the presence of a thick layer of old road fill at the top of the slope, and the shallow depth of bedrock lower on the slope, a combination of foundation types was used. The uphill foundations were large diameter drilled piles that not only supported the house, but also provided lateral stability for old road fill overlying the bedrock. The downslope foundations were conventional footings, each of which contained two grouted anchors drilled into the bedrock to provide overturning resistance. A small drill rig was used to install the grouted anchors. A large crane had to be used to place the drill rig on a narrow bench created on the steep slope.
